As a system for contactlessly sending electric power to service vehicles and cars in a factory, as described in Patent Literature 1, there is proposed a contactless power supply system in which electric power is sent from a primary coil to a secondary coil by arranging the primary coil and the secondary coil with a space in between and providing a resonance coil (tertiary coil) having a capacitor for resonance connected thereto on a secondary side.
Also, in Patent Literature 2, there is proposed a contactless power supply system for a ground moving body in which rise in voltage of pickup coils is regulated by regarding a power feed line arranged along a travel path as a primary side, regarding pickup coils wound around iron cores provided to a ground moving body as a secondary side, forming a resonance circuit by parallelly connecting a resonance capacitor to output terminals of the pickup coils, parallelly connecting a saturable reactor to the pickup coils, self-inductance of the saturable reactor lowering by being magnetically saturated upon rising of voltage of the pickup coils, and increasing electric current flowing to the saturable reactor in association with lightening of weight of a load.